Journal of the Korean Society of Radiology (한국방사선학회논문지)

The Korean Society of Radiology (한국방사선학회)
권호 표지
DOI QR코드

DOI QR Code

Evaluation of Reproducibility According to Variation of Coil Channel in Quantitative Evaluation Using Synthetic MR

Synthetic MR을 이용한 정량적 평가에서 Coil channel 수 변화에 따른 재현성 평가

  • Kwon, Soon-Yong (Department of Radiology, Konkuk University Medical Center) ;
  • Kim, Seong-Ho (Department of Radiology, Konkuk University Medical Center)
  • 권순용 (건국대학교병원 영상의학과) ;
  • 김성호 (건국대학교병원 영상의학과)
  • Received : 2017.09.15
  • Accepted : 2017.10.31
  • Published : 2017.10.31
Download PDF
⟨ Previous Next ⟩

Abstract

T1, T2 relaxation time and relaxation rates were measured and analyzed according to the change of RF coil channel number of MAGiC sequence. T1, T2, R1 and R2 maps were obtained by using MAGiC sequence with phantom (1.0, 0.6, 0.2, 0 mM) on the RF coil with channel number of 1, 8, 16 and 32 respectively. T1, T2, R1, R2 values and relaxation rates were measured for each channel number and concentration, and Relaxivity was calculated according to each concentration. T1, T2, R1, and R2 values were measured in each coil. There was no significant difference between T1 and R1 values (p> 0.05). However, T2 and R2 values were significantly different (p <0.05). In the post-analysis results, T2 value was significantly different from that measured on 1, 8, 16, and 32 channel coils (p <0.05) and There was no difference between 8, 16, and 32 channel coils (p> 0.05). The R2 value was significantly different from that measured on the 8, 16, and 32 channel coils in the 1 channel coil, and the results on the 8 channel coils and the 16 channel coils showed a significant difference (P <0.05). In conclusion, T1 and R1 values were not significantly different according to the number of channels in the coil, but T2 and R2 values were significantly different. Therefore, when quantitative measurement of T2 and R2 values using the MAGiC sequence, the same number of coils should be used for reproducibility.

최신 영상 기법인 MAGiC sequence의 RF coil channel 수 변화에 따른 T1, T2 이완 시간 및 T1, T2 이완율을 측정하여 분석하였고 그에 따른 재현성을 평가하였다. Channel 수가 각각 (1, 8, 16, 32)channel 인 RF coil에 조영제 phantom(1.0, 0.6, 0.2, 0mM)을 위치시키고 MAGiC sequence를 이용하여 T1, T2, R1, R2 map을 획득하였다. 그리고 각각의 channel 수와 농도별로 T1, T2, R1, R2 value 그리고 relaxation rate를 측정하였고 이를 기반으로 각 농도에 따른 Relaxivity를 구하였다. 각각의 coil에서 T1, T2, R1, R2 value를 측정한 결과 T1, R1 value는 coil간의 유의한 차이가 없었다(p>0.05). 하지만 T2, R2 value는 유의한 차이가 있는 것으로 나타났다(p<0.05). 사후분석 결과에서는 T2 value의 경우 1 channel coil에서 측정한 결과가 8, 16, 32 channel coil에서 측정한 결과와 유의한 차이가 나타났고(p<0.05) 8, 16, 32 channel coil간의 차이는 나타나지 않았다(p>0.05). R2 value의 경우도 마찬가지로 1 channel coil에서 측정한 결과가 8, 16, 32 channel coil에서 측정한 결과와 유의한 차이가 나타났으며 또한 8 channel coil에서 측정한 결과와 16 channel coil에서 측정한 결과가 유의한 차이가 나타났다(p<0.05). 결론적으로 T1, R1 value는 coil의 channel 수 변화에 따른 차이가 크지 않지만 T2, R2 value는 큰 차이를 나타냈다. 따라서 MAGiC sequence를 이용하여 T2, R2 value를 정량적으로 측정할 경우 재현성을 위해 동일한 channel 수의 coil을 사용해야 할 것으로 사료된다.

Keywords

References

  1. Kevin J. Chang, Hernan Jara, "Application of quantitative T1, T2 and proton density to diagnosis," APPLIED RADIOLOGY, January 19, 2005.
  2. Y. Wang, L. de Rochefort, T. Liu, Bryan Kressler, "Magnetic source MRI: A new quantitative imaging of magnetic biomarkers," 2009 Annual International Conference of the Institute of Electrical and Electronics Engineers in Medicine and Biology Society, pp. 53-56, 2009.
  3. aTraber F, Block W, Lamerichs R, Gieseke J, Schild HH, "1H Metabolite Relaxation Times at 3.0 Tesla: Measurements of T1 and T2 Values in Normal Brain and Determination of Regional Differences in Transverse Relaxation," JOURNAL OF MAGNETIC RESONANCE IMAGING, Vol. 19, Issue 5, pp. 537-545, 2004 https://doi.org/10.1002/jmri.20053
  4. R. Maitra, J. J. Riddles, "Synthetic Magnetic Resonance Imaging Revisited," the Institute of Electrical and Electronics Engineers Transactions on Medical Imaging, Vol. 29, Issue 3, pp. 895-902, 2010.
  5. Marcel Warntjes, "New Technology Allows Multiple Image Contrasts in a Single Scan," SIGNA pulse of MR, Spring Issue, pp. 6-10, 2015
  6. W. B. Jung, M. J. Kang, D. B. Son, Y. J. Kim, Y. M. Lee, Y. H. Kim, C. K. Eun, C. W. Mun, " Reproducibility Analysis of Brain Volumetry Measured from Inter MR Scanner of Multi-Institute," Journal of the Korean Society of Magnetic Resonance in Medicine, Vol.16, No.3, pp. 243-252, 2012. https://doi.org/10.13104/jksmrm.2012.16.3.243
  7. Ray H. Hashemi, William G. Bradly, Jr., Christopher J. Lisanti, MRI The Basic 2nd Edition. Part I: Basic Concept, LIPPINCOTT WILLIAMS & WILKINS, 2004.
  8. E. L. Barbier, L. Lamalle, M. Decorps., "Methodology of brain perfusion imaging," Journal of Magnetic Resonance Imaging, Vol. 13, Issue 4, pp. 496-520, 2001. https://doi.org/10.1002/jmri.1073
  9. Magnetic Resonance Fingerprinting - a promising new approach to obtain standardized imaging biomarkers from MRI, European Society of Radiology (ESR) , Vol. 6, No. 2, pp. 163-165, Apr 2015. https://doi.org/10.1007/s13244-015-0403-3
  10. A. Hagiwara, M. Hori, K. Yokoyama, M.Y. Takemura, C. Andica, T. Tabata, K. Kamagata, M. Suzuki, "Synthetic MRI in the Detection of Multiple Sclerosis Plaques," December 8, 2016.
  11. T. Helmersson, "Evaluation of Synthetic MRI for Clinical Use," Linkopings universitet, Institutionen for medicin och halsa, pp. 1-4, 2010.
  12. H. K. Jeong, S. H. Kim, C. H. Kang, S. H. Lee, M. K. Kim, Y. Lee, H. C. Kim, "Signal Change of Iodinated Contrast Agents in MR Imaging," Journal of the Institute of Electronics and Information Engineers, Vol. 53, No. 12, December 2016.
  13. Giada Zoccatelli, Franco Alessandrini, Alberto Beltramello "Advanced magnetic resonance imaging technique in brain tomor surgical planning," J. Biomedical Science and Engineering, January 14, pp. 403-417, 2013.
  14. Garry E. Gold, Brian Suh, Anne Sawyer-Glover, Christopher Beaulieu, "Musculoskeletal MRI at 3.0 T: initial clinical experience," American Journal of Roentgenology, Vol.183, pp. 1479-1486, 2004. https://doi.org/10.2214/ajr.183.5.1831479
  15. Bent O. Kjos, Richard L. Ehman, Michael Brant-Zawadzki, "Reproducibility of T1 and T2 Relaxation Times Calculated from Routine MR Imaging Sequences: Phantom Study," American Journal of Neuroradiology Vol. 6, pp. 277-283, March/April 1985.
  16. Gregory Chang, Graham C. Wiggins, Ding Xia " Comparison of a 28-Channel Receive Array Coil and Quadrature Volume Coil for Morphologic Imaging and T2 Mapping of Knee Cartilage at 7T," Journal of Magnetic Resonance Imaging, Vol. 35, pp. 441-448, 2012. https://doi.org/10.1002/jmri.23506